Strain-insulator.



slack inthe conduti unirsi). srarns PATENT oiuuon. L

WILLIAM' SCHAAKE. 0F PITTSBURGH, PENNSYLVANIA, ASSIGNCR TO WESTINGHOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION O F PENNSYLVANIA.

STRAIN-INSULATOR.

Specification of Letters latent. Patented Nov, 2S, 1911.

Application led January 26, 1910. Serial No. 540,236.

vand State of Pennsylvania, have invented a new and useful Improvement in Strain-Insulators, of which the following is a specilication.

'My invention relates to electric line material and it has special reference to strain insulators. I

The object of my invention is to provide a simple and durable device of the class4 above indicated that `shall be adjustable in order to avoid the necessity for a turn buckle or other auxiliary means for taking up the with which the device is employed.

Strain insulators, severally comprising arod or bar lof wood and iron or steel end members, have frequently been employed iny connection with electric line'structures, but it has 4usually been necessary to provide `some independent. means for adjusting lthe tension in the conductor wit-li which the insulator was employed. Y

According to my present invention, I provide a strain insulator of the wood-bar construction, having one end so formed as to provide an adjustment of the overall length of the device, thereby obviating the necessity for auxiliary apparatus. n

Figure 1 of the accompanying drawings is a partially sectionalelevation of a strain insulator constructed in accordance with my invention and Figs. 2, 3, 4 and 5 are detail views of the structure shown in Fig. 1.

Referring to the drawings, the'structure here'showncomprises a bar 1 of wood or other suitable insulating material, a swaged member 2 Which'grips one end of the bar 1 and an adjustable member 3 which grips the opposite end of the bar l.

The member 2 is -provided with a ring projection 2 by which the insulator may be attached to a line conductor or cable and it is first constructed in the form of a cup,

having parallel sides and is swaged into the form shown in- Fig. l of the drawings after it is .in position on the end of the bar l. The ends of the bar Aare truste-conical in order to offer a very great resistance to the removal of the ends after the swaging process has been completed,`

The adjustable member 3 comprises a hol low cylinder Ll'having inwardly extending projections 5 intermediate its ends, as shownl in Figo of the drawings and an inwardly projecting iiange 6 at one end, which consti- .tutes the walls of a hexagonal opening 7 to receive a nut 8, as shown in Fig. l. In addition to the cylinder' 4t, the member 3 comprises an eye bolt 9, which is screw threaded so that it may be adjusted into and out of the nut S by rotating the nut.

The nutS is provided with lateral pro-` jections l0 at one end which' are adaptedto register with the spaces between the projections 5 of the cylinder t, when assembling the parts, and to engage the flange 6 when they are assembled.

It is essential to provide a stop of some kind against which the end of the bar l may abut in order that said bar may be lirmly seated vwhen the swagin g process is complete. Fiutherniore, it is desirable to permit the rotation of the nut- 8 within the cylinder 4 without allowing it to be detached therefrom after the insulator parts are assembled.

In order to accomplish these results, I provide the nut with the flange projection l0 which cooperates with theiiange G on ,the cylinder il and so arrange they projections 5 on the inner surface of the cylinder 4 that the projections l0 of the nut may pass between them in assembling the parts. A washer il rests against the projection and 'forms a satisfactory stop against which the the cylinder 4 may be varied over relatively wide limits by rotating the bolt or thenut 8 and,- consequently, it is possible, after the insulator is connected to a circuit conductor. to'take up -a certain amount of slack and to putthe insulator under tension without making use of any auxiliary apparatus.

It is evident. that structural .modifications maybe effected within the spirit and scope of my invention, and I desire that only `such limitations shall be imposed as are indicated in the appended claims.

I claim as my invention:

l. A strain insulator comprising a bar of insulating material having enlarged ends of frusto-conical form, a metal cap swaged upon one of said enlarged ends and having an eye projection, a cylindrical member having its inner end swaged to the other end of said bar and havin an internal flange at its outer end, a rotata le nut having` an expanded inner end located in said cylindrical member, and an eye-bolt adapted to adjusted longitudinally by the rotation of said nut.

2. A n insulator for electric lines comprising a bar of insulating material, a cylindrical member the inner end of which is swaged upon one end of said bar and has internal projections against which the bar abuts and the outer end of which has an internal flange, a rotatable nutf projecting from 'the outer end of the cylindrical member and having external pro'ections to engage its 1 flange, and an eyeolt coperating with said nut.

3. A u insulator for electric lines comprising a bar of insulating material, a cylindrical member the inner end of which is swaged upon one end of said bar and has inner proj ections, and the outer end of which is p'rovided with an internal flange against which the bar abuts, a rotatable nut projecting out- Wardly from the cylindrical member and having lateral projections adapted to engage said internal flange, and an eyebolt coperating with said nut.

4. An insulator for electric lines comprising a bar of insulating material, a flanged cylindrical member swaged upon one end of 40 subscribed my name this 19th day of Jan.,

' WILLIAM SCHAAKE. lVitnesses E. W. P. SMITH, B. B. Hines. 

